The hardness came back into his eyes and he looked away.
You get used to knowing the different types of hardness and thickness.
With repeated hammering, drawing out and annealing, it gains much in strength and toughness, and the addition of a very minute quantity of carbon converts it into steel, less tough, but of the keenest hardness.
The bearing of the pivot is called a step or footstep. Pivots require great hardness, and are usually made of steel.
The characters of softness or hardness, dryness or moisture, &c., are taken account of in these classifications.